Spearguns are used underwater for firing a spear at fish or other targets. Although pneumatically driven spearguns are known, most common spearguns use elastic bands for accelerating the spear. Spearguns typically comprise a barrel, which, for example, has an oblong body and a spear track for directly receiving a spear. The spear track is usually formed as a channel on the outer surface of the barrel. The spear can be inserted into the spear track, which guides the spear while it is being accelerated by the elastic bands, for example, when the speargun is fired. Spearguns also typically comprise a handle unit which can, for example, comprise a handle and a finger trigger usually located in front of the handle. The handle unit is connected to the barrel. Spearguns are also typically provided with a trigger unit having a housing containing a trigger mechanism for releasing the spear through activation of the finger trigger. The trigger mechanism is usually used to fix the spear and the tensioned elastic band in place and to release them when the finger trigger is activated.
In spearguns of the type employing elastic bands for the acceleration of the spear, multiple elastic bands are typically used in a single speargun. As the elastic band or bands of the speargun have to be tensioned manually and underwater by the user of the speargun, the use of more than one elastic band facilitates loading of the speargun while multiple elastic bands can be used to collectively accelerate the spear with the necessary force. When the speargun is fully loaded, i.e. when the elastic bands are tensioned, the full elastic load of all the bands combined rests on the barrel, which needs to be sufficiently strong to withstand these forces. Especially with larger models of spearguns having very long barrels and multiple strong elastic bands, these forces can lead to bending or even breakage of the barrel.
The handle of the speargun is typically either in a position at the rear of the barrel or offset from the rear end of the barrel in the direction toward the middle of the barrel. Thus, there are either spearguns having their handle in a middle position or spearguns having the handle in a rear position. Both positions of the handle have different advantages and disadvantages in the handling of the speargun, for example when aiming at a target.
Another problem of conventional spearguns is that a lot of sand or other suspended solid particles are washed into the trigger mechanism, which is impossible to avoid. These solids can lead to a jamming of the trigger mechanism, which leads to a failure of the speargun when the user tries to fire. This can even be dangerous if the user tries to remove such a jam and accidentally sets off the tensioned elastic bands.